the assert message's file and line number gives some clue as to the
real location of the problem.

Added similar assertions to list.h.

implement the -e option.

(Thanks to Jim McQuillan for this suggestion.)

(Problem observed by Clay McClure in VMware Fusion.)

order in which they occur.

Conflicts:

	src/include/compiler.h
	src/include/readline/readline.h

created by strings branch merge. resolved.

require that we use drive 0x80, so it should probably be the default.

out-of-tree driver code.